A7 __B7 五、發明説明1() 發明背景 發明範菌 ' 本發明與一種改良的晶圓支持架有關，當晶圓被硏磨 或拋光時，該支持架真空支持半導體晶圓。 相關技術說明一 習用上1當晶圓’如砂晶圓或碑化嫁晶圓，被硏磨或 拋光時’ _由微粒燒·結體所形成之晶圓支持架因具有高_強度 且不因機械加工的壓力而變形，被使用於晶圓表面精確的 機械加工，使晶圓表面成爲高度平坦的表面。 經濟部中央標準局員工消費合作社印製 而且，有一種習知的支持架，該種支持架有數個不同 特性的區域。如圖5所示，該支持架5 1中，用來支持晶 圓W的晶圓支持表面由多孔性微粒燒結體5 2所形成，且 非多孔性微粒燒結體5 3圍繞多孔性微粒燒結體5 2。多 孔性微粒燒結體5 2以某種製程所製，其中，燒結微粒， 使得結果的燒成體成爲多孔性。非多孔性微粒燒結體5 3 以某種製程所製，其中，燒結微粒，使得結果的燒成體成 爲緻密或非多孔性。排氣道5 4與多孔性微粒燒結體5 2 相連接。利用排氣方式經由排氣道5 4，晶圓W被以真空 方式支持。於此支持架中，爲了界定真空區域，多孔性微 粒燒結體5 2的外直徑通常較晶圓W的直徑爲小，所以真 空區域由外部的非多孔性微粒燒結體5 3及晶圓W所組成 〇 通常，即使當支持架的支持表面是平坦的，若晶圓及 -4- (請先鬩讀背面之注意事項再填寫本頁) 本紙張尺度適用中國國家標準（.CNS ) A4規格（210X297公釐） 經濟部中央標準局員工消費合作社印製 A7 B7 五、發明説明2() 支持架的支持表面間有如灰塵之外來物質時，以支持架支 持的晶圓會形變。這成爲機械加工精確度劣化的原因。 於上述真空式晶圓支持架的情形下，沒有問題發生， 因爲多孔性微粒燒結體5 2及晶圓W間的灰塵，經由多孔 性微粒燒結體5 2表面的孔隙吸入。然而，因爲非多孔性 微粒燒結體5 3支持晶圓之外圍部分，非多孔性微粒燒結 體5 3及晶圓W之間的灰塵未被吸入，晶圓w可能以形變 的狀態被支持。 當形變狀態的晶圓被機械加工時，晶圓表面的平坦度 會劣化。 再者，多孔性微粒燒結體5 2支持的晶圓部分與非多 孔性微粒燒結體5 3支持的晶圓部分，因爲機械加工壓力 造成的晶圓W形變的數量不同。因爲多孔性微粒燒結體 5 2支持的晶圓部分之由負載引起的形變量大於非多孔性 微粒燒結體5 3支持的晶圓部分之形變量，中央部分機械 加工之原料移除（由機械加工移除的材料量）變得較小。 因此，機械加工過的晶圓有不夠平坦的問題，其中，晶圓 中央部分的厚度厚於晶圓的其餘部分。 因此’對於避免機械加工精確性劣化的技術有強烈的 需要’該種機械加工精確性的劣化有可能另外由灰塵的沾 染或類似物引起的晶圓形變造成，或由進行機械加工時產 生形變的不平坦所造成。 發明槪要 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐） -5 - ----Λ-----裝------訂------"線 - (請先閱讀背面之注意事項再填寫本頁) 經濟部中央標準局員工消費合作社印製 A7 B7 五、發明説明3() 由於上述的缺點構思本發明。本發明的一個目的在提 出一種晶圓支持架，該支持架可避免機械加工精確性的劣 化，該種機械加工精確性的劣化有可能另由灰_或_似 物的沾染引起的晶圓形變所造成，或進行機械扭Li.i寺產生 形屢典不爷坦-所造成。 爲了達到上述目的，本發明提出一種晶画支持架，該 晶圓支持架具有多孔性支持表面，當晶圓被硏磨或拋光時 ，該支持架用來真空支持半導體晶圓。支持表面中央區域 的孔隙度較外部區域爲大，支持表面的外部區域圍繞.中央 區域，且中央區域的外直徑較晶圓的直徑爲小，而外部區 域的外直徑較晶圓的直徑爲大。 因爲爲了以多孔性表面支持整個晶圓，外部區域的外 直徑大於晶圓的直徑，可抑屬施加壓力時晶圓形變量的不 一致。另外，因爲如灰塵之外來物質容易於多孔性表面經 由孔隙被吸入，晶圓變得不容易形變。 而且，因爲中央區域的外直徑小於晶圓的直徑，中央 區域可被用來當成真空區域。 較佳的是，排氣道與中央區域連接，不與外部區域連 接。 因爲排氣道只與中央區域連接，中央區域有大的孔隙 度，且排氣利用排氣道進行，真空區域的、真空度可被增—如 以改進支持的性能。 較佳的是，中央區域孔隙的平均直徑爲6 〇 - 3 0 0 微米’且外部區域孔隙的平均直徑爲2 - 5 0微米。 本紙張尺度適用中國國家標準（CNS ) A4規格（21〇X297公釐] -6 - - ---Π------裝------訂-------線 - (請先聞讀背面之注意事項再填寫本頁) 經濟部中央標隼局員工消費合作社印製 A7 B7 五、發明説明4() 中央區域孔隙的平均直徑設於6 0 — 3 0 0微米的範 圍的原因是，若中央區域孔隙的平均直徑落在6 0 -3 0 0微米的範圍內，中央區域的孔隙可提供吸入灰塵或 類似物的高效能及可靠的排氣性。外部區域孔隙的平均直 徑設於2 - 5 0微米的範圍的原因是，若外部區域孔隙的 平均直徑落在2 - 5 0微米的範圍內，外部區域可以可靠 的界定出真空區域，以及可以避免機械加工中造成平坦度 的缺點。即，若外部區域孔隙的平均直徑設於5 0微米或 更大，無法可靠的界定出真空區域，導致支持力的降低： 且若外部區域孔隙的平均直徑設於2微米或更小，增加平 坦度的失敗。 較佳的是，中央區域的外直徑爲晶圓直徑的5 0 -9 9 %，且外部區域的外直徑爲晶圓直徑的1 0 0 — 2 0 0 %。 當中央區域的外直徑設於上述範圍內時，可得到滿意 的真空支持性能。當中央區域的外直徑設於上述範圍內時 ，可避免不合理的增加支持架的尺寸。 本發明中，晶圓支持架的支持表面分爲中央區域及外 部區域；中央區域的孔隙度較外部區域的孔隙度爲大；且 中央區域的外直徑較被支持的晶圓的直徑爲小，而外部區 域的外直徑較晶圓的直徑爲大。因此，整個晶圓哥裤多孔 性表面支持，及可JL制進j?機轉加工晶圓形變量的 不一致。.另外. . .，可I黑.多4L性.裘通由孔隙吸入如灰塵之 外來^物·要。因爲不_ 一致的形變及沾染生速物質造成的不利 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐） ^7~~ ”------@-批衣------1T-----!)/0 一 (諳先聞讀背面之注意事項再填寫本頁) 經濟部中央標準局員工消費合作社印製 A7 B7 五、發明説明5() 影響可被減少，晶圓變得不容易形變.，導致機械加工精確 性的增加。 . 再者，避免外來物質附著的氣式淨化設備及淸潔支持 架的系統因爲變得沒有必要使用，可以簡化整個設備。 圖式簡要說明 圖1爲依照本發明之晶圓支持孥之直立截面圖； 圖2爲說明圖式，顯示依照本發明之晶圓支持架使用 於拋光過程中的情形； 圖3爲說明圖式，顯示依照本發明之晶圓支持架使用 於硏磨過程中的情形； 圖4之圖式顯示硏磨測試的結果，其中，使甩本發明 之晶圓支持架之以硏磨過程硏磨之晶圓形狀與使用習用晶 圓支持架之以硏磨過程硏磨的晶圓相比較；以及 圖5爲習用晶圓支持架之直立截面圖。 主要元件對照表 ' 5 1 支持架· 52 多孔性微粒燒結體 53 非多孔性微粒燒結體 5 4 排氣道 1 晶圓支持架 2 第一多孔性微粒燒結體 3 第二多孔性微粒燒結體 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐） -8 - (請先閱讀背面之注意事項再填寫本頁) ---裝------訂--- f A7 ________B7 五、發明説明6() 4 非多孔性燒結體 5 排氣道 6 拋光頭 8 拋光墊 7 抛光台 10 硏磨頭 11 硏磨石 經濟部中央標隼局員工消費合作社印製 較佳實施例說明 將參考圖示詳細說明本發明之較佳實施例。 依照本發明之晶圓支持架用來支持如矽晶圓或·砷化鎵 晶圓之易脆晶圓，而晶圓的表面被硏磨或拋光。設計晶圓 支持架，經由精確的支持晶圓，改進晶圓的平坦度。 即，如圖1所示，依照本發明之晶圓支持架1的支持 表面分爲依次從支持表面的中央至外部之同心圓環狀區域 A，B，C。區域A，B及C分別由第一多孔微粒燒結體 2，第二多孔微粒燒結體3，及非多孔性燒結體4所形成 。形成中央區域A的第一多孔微粒燒結體2的孔隙度與形 成外部區域B的第二多孔微粒燒結體3的孔隙度不同，外 部區域B緊臨中央區域A的外部。形成最外部區域C的非 多孔性燒結體4爲緻密或非多孔性。 中央區域A的孔隙的平均直徑爲6 0 — 3 0 0微米以 提供相對較大的孔隙度’且外部區域b的孔隙的平均直徑 爲2 - 5 0微米以提供小於中央區域A之孔隙度。中央區 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐） -9 - (請先閱讀背面之注意事項再填寫本頁) ---r-l„__— ---訂--- /線--Λ--ΙΊ{— 經濟部中央標準局員工消費合作社印製 A7 B7 五、發明説明7() 域A的外直徑小於晶圓之直徑（5 0 — 9 9 % )，而外部 區域B的外直徑大於晶圓的直徑（100-200 %)。 排氣道5作爲真空管用，形成於非多孔性燒結體4之 底部，所以排氣道5的內部端點通達第一多孔微粒燒結體 2的底部，第一多孔微粒燒結體2形成中央區域A。晶圓 W置於支持架1後，中央區域A的氣體經由排氣道5排出 ，以便真空支持晶圓。 因爲排氣道5不通達外部區域B，中央區域A的真空 度可以被增加。 此種真空式支持架的優點爲，即使當晶圓W及支持架 支持表面之間的空間進入灰塵或類似物時，灰塵或類似物 於多孔性表面經由孔隙以排氣方式被吸入，以避免晶圓因 爲灰塵或類似物而形變。 由於前述之說明，本發明之支持架1的設計使得整個 晶圓由多孔性表面支持，以便，完全利用真空式支持架的優 點。 再者，因爲中央區域A的孔隙度大於中央區域外之外 部區域B的孔隙度，中央區域A中可以有效的產生真空區 〇 相反的，當中央區域A與外部區域B有相同的孔隙度 ，產生一個問題，即，若孔隙的平均直徑增加，真空區不 會被形成，導致支持力的減少，而且若孔隙的平均直徑減 少，吸入灰塵或類似物的性能劣化1則會產生因灰塵或類 似物造成的晶圓劣化。 本紙張尺度適用中國國家標準（CNS > A4規格（210X297公釐、 "1〇 _ —-Jf.--^----裝-- - (請先聞讀背面之注意事項.再填寫本頁) 訂 2. 經濟部中央標準局員工消費合作社印製· A7 B7 五、發明説明8() 依照本發明之晶圓支持架由以下的方法製造。商業上 可得之由氧化鋁陶瓷形成的緻密性微粒燒結體有非常低的 孔隙度，該緻密性微粒燒結體被壓成顆粒，而後將顆粒分 爲一組由大顆粒組成及一組由小顆粒組成。大顆粒組的顆 粒被用來當成第一多孔性微粒燒結體的材料，而小顆粒組 的顆粒被用來當成第二多孔性微粒燒結體的材料。各組顆 粒混合黏結劑及玻璃，黏結劑及玻璃作爲黏著劑用，且燒 結混合物得到燒結體。燒結期間，黏結劑及玻璃部分蒸發 形成孔隙。因此，因爲顆粒大小及燒結條件的不同，第一 及第二多孔性微粒燒結體有不同的孔隙度。緻密（非多孔 性）的微粒燒結體以習知的方式製造。之後，第一多孔性 微粒燒結體，第二多孔性微粒燒結體，及緻密性或非多孔 性微粒燒結體利用融熔玻璃使之結合在一起。最後，支持 表面以機械方式加工成平坦表面.，因此完成晶圓支持架。 圖2顯示一例，其中依照本發明之支持架1被施予拋 .光過程。 即，以支持架1真空支持之晶圓W附著於拋光頭6， 且晶圓W被附著於拋光台7之拋光墊8拋光。拋光過程中 ，即使當灰塵或類似物進入支持架1之支持表面與晶圓W 間之空間時，灰塵或類似物會被吸入，因此不‘會引起如晶 圓形變之不利影響。再者，即使當機械加工的壓力作用於 晶圓W時，中央區域A及外部區域B之間不會產生形變量 的不同，因此晶圓W的平坦度不會劣化。 圖3顯示一例，其中，依照本發明之支持架1被施予 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐） -11 - ' ' (請先閱讀背面之注意事項再填寫本頁) --裝— -訂 —---I.--/ 線--,--J----- 經濟部中央標準局*；工消費合作社印製 A7 B7 __ 五、發明説明9() 硏磨過程。 即，於此情形，晶圓W被支持架1真空支持，'該支持 架1附著於硏磨頭1 0，且晶圓W被硏磨石1 1硏磨。同 樣於此情形下，晶圓W可被機械加工爲具有高度平表面。 兩例中，優點爲無須使用如爲避免外來物質沾染之氣 式淨化設備或淸潔支持架系統的輔助設備。 實例 製造一種支持架，使中央區域A的外直徑爲1 3 0 mm以及孔隙的平均直徑爲1 〇 〇微米，而外部區域B的 外直徑爲1 6 0 m m以及孔隙的平均直徑爲1 0微米。晶 圓W的直徑爲1 5 Omm且利用支持架（實例）硏磨。而 且，製造習知之支持架，使中央多孔性的微粒燒結體5 2 之外直徑爲1 4 0mm以及孔隙的平均直徑爲1 0 0微米 ，而外部緻密（非多孔性）的微粒燒結體5 3之外直徑爲 1 6 0 m m。相同的晶圓W利用支持架硏磨（比較例）。 實例使用本發明之支持架與比較例中使用習知的支持 架，以機械加工的精確度做比較。圖4明顯的顯示出硏磨 晶圓中厚度的分布，當使用本發明之支持架時，將各晶圓 機械加工爲高度平坦的表面，不會引起平坦度的失敗。而 ，實例中的1 0 0個晶圓，無一有平坦度的失敗，比較例 中1 0 0個晶圓中有1 5個平坦度的失敗。 以上說明之實施例中，中央區域A及外部區域B分別 有一致的孔隙度。然而，各區域A及B可被區分爲次區域 本紙張尺度適用中國國家標準（CNS ) Λ4規格（210X297公釐) -12- (請先閲讀背面之注意事項异填寫本頁) 訂 S87110 at B7 五、發明説明) ’以便逐漸的改變孔隙度。以上說明的實施例只是一個例 子’以及那些具有與增錄之專利申請範圍中說明的'結構相 同者及提出相同作用及效果者，皆包含於本發明之範疇內 I. -,lif---„--^--^裝一i I (請先閱讀背面之注意事項再填寫本頁) -訂 經濟部中央標準局員工消費合作社印製 一尺 I張 紙 準 標 家 國 國 中 5 |適 " |釐 公 -13-A7 __B7 V. Description of the invention 1 () Background of the invention The invention relates to an improved wafer support frame. When the wafer is honed or polished, the support frame vacuum supports the semiconductor wafer. Relevant technical descriptions are used. When a wafer is 'honed or polished, such as a sand wafer or a tablet wafer,' _ The wafer support frame formed by particle firing and structure has high strength and does not Deformed by the pressure of machining, it is used for precise machining of the wafer surface, making the wafer surface a highly flat surface. Printed by the Consumer Standards Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs. Furthermore, there is a conventional support frame that has several areas with different characteristics. As shown in FIG. 5, in the support frame 51, a wafer supporting surface for supporting the wafer W is formed by a porous fine particle sintered body 52, and a non-porous fine particle sintered body 5 3 surrounds the porous fine particle sintered body 5 2. The porous porous particle sintered body 52 is produced by a certain process, in which the fine particles are sintered to make the resulting fired body porous. The non-porous fine particle sintered body 5 3 is produced by a process in which fine particles are sintered so that the resulting fired body becomes dense or non-porous. The exhaust duct 54 is connected to the porous fine particle sintered body 5 2. The wafer W is supported in a vacuum manner via the exhaust path 54 through the exhaust method. In this support frame, in order to define a vacuum region, the outer diameter of the porous fine particle sintered body 52 is generally smaller than the diameter of the wafer W. Therefore, the vacuum region is defined by the outer non-porous fine particle sintered body 5 3 and the wafer W. Composition 〇 Generally, even when the support surface of the support frame is flat, if the wafer and -4- (please read the precautions on the back before filling this page) This paper size applies the Chinese National Standard (.CNS) A4 specifications ( 210X297 mm) A7 B7 printed by the Consumer Cooperative of the Central Bureau of Standards of the Ministry of Economic Affairs 5. Description of the Invention 2 () When there is foreign matter between the support surfaces of the support frame, the wafers supported by the support frame will deform. This becomes the cause of deterioration in the accuracy of machining. In the case of the above-mentioned vacuum type wafer support frame, no problem occurs because the dust between the porous fine particle sintered body 52 and the wafer W is sucked through the pores on the surface of the porous fine particle sintered body 52. However, because the non-porous fine particle sintered body 53 supports the peripheral portion of the wafer, the dust between the non-porous fine particle sintered body 53 and the wafer W is not sucked, and the wafer w may be supported in a deformed state. When a deformed wafer is machined, the flatness of the wafer surface is deteriorated. Furthermore, the wafer portion supported by the porous fine particle sintered body 52 and the wafer portion supported by the non-porous fine particle sintered body 52 are different in the amount of wafer W deformation due to machining pressure. Since the deformation of the wafer portion supported by the porous fine particle sintered body 5 2 caused by the load is larger than that of the wafer portion supported by the non-porous fine particle sintered body 52, the machining of the central portion of the raw material is removed (by machining Amount of material removed) becomes smaller. Therefore, the machined wafer has a problem of insufficient flatness, in which the central portion of the wafer is thicker than the rest of the wafer. Therefore, 'there is a strong need for a technique to avoid deterioration of the accuracy of machining'. This deterioration of the accuracy of machining may be caused by the contamination of dust or the like due to crystal circle deformation, or by deformation during machining Caused by unevenness. The invention requires that the paper size is applicable to the Chinese National Standard (CNS) A4 specification (210X297 mm) -5----- Λ ----- installation ------ order ------ " line -(Please read the notes on the back before filling out this page) A7 B7 printed by the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs 5. Description of the invention 3 () The present invention was conceived due to the above-mentioned shortcomings. An object of the present invention is to provide a wafer support frame, which can avoid the deterioration of the accuracy of machining. Such deterioration of the accuracy of machining may possibly be caused by the contamination of ash or the like. The change is caused by the mechanical twist of Li.i Temple, which is caused by the repetitive dynasty. In order to achieve the above object, the present invention provides a crystal painting support frame. The wafer support frame has a porous support surface. When the wafer is honed or polished, the support frame is used to vacuum support a semiconductor wafer. The central region of the supporting surface has greater porosity than the outer region, and the outer region of the supporting surface is surrounded. The central region, and the outer diameter of the central region is smaller than the diameter of the wafer, and the outer diameter of the outer region is larger than the diameter of the wafer. . Because in order to support the entire wafer with a porous surface, the outer diameter of the outer region is larger than the diameter of the wafer, which can suppress the inconsistency of the crystal circular variable when pressure is applied. In addition, since foreign substances such as dust are easily sucked into the porous surface through the pores, the wafer becomes difficult to deform. Moreover, because the outer diameter of the central region is smaller than the diameter of the wafer, the central region can be used as a vacuum region. Preferably, the exhaust duct is connected to the central region and not connected to the outer region. Because the exhaust duct is only connected to the central region, the central region has a large porosity, and the exhaust is carried out using the exhaust duct, the vacuum in the vacuum region can be increased—for example, to improve the support performance. Preferably, the average diameter of the pores in the central region is 60-300 micrometers' and the average diameter of the pores in the outer region is 2-50 micrometers. This paper size is applicable to China National Standard (CNS) A4 specification (21 × 297 mm) -6----Π ---------------------------- (Please read the notes on the back before filling out this page) Printed by the Consumers' Cooperative of the Central Bureau of Standards of the Ministry of Economic Affairs A7 B7 V. Invention Description 4 () The average diameter of the pores in the central area is set at 60-300 microns The reason for the range is that if the average diameter of the pores in the central region falls within the range of 60-300 micrometers, the pores in the central region can provide high efficiency and reliable exhaustability for sucking dust or the like. The reason why the average diameter is set in the range of 2-50 micrometers is that if the average diameter of the pores in the outer region falls within the range of 2-50 micrometers, the outer region can reliably define the vacuum region, and can avoid the problems caused by machining The disadvantage of flatness. That is, if the average diameter of the pores in the outer region is set to 50 microns or more, the vacuum region cannot be reliably defined, which results in a reduction in the support force: and if the average diameter of the pores in the outer region is set to 2 micrometers or Smaller, increase the failure of flatness. , The outer diameter of the central area is 50 to 9% of the wafer diameter, and the outer diameter of the outer area is 100 to 2 0% of the wafer diameter. When the outer diameter of the central area is set within the above range Satisfactory vacuum support performance can be obtained. When the outer diameter of the central region is set within the above range, an unreasonable increase in the size of the support frame can be avoided. In the present invention, the support surface of the wafer support frame is divided into the central region and the outside The porosity of the central region is larger than the porosity of the outer region; and the outer diameter of the central region is smaller than the diameter of the wafer being supported, and the outer diameter of the outer region is larger than the diameter of the wafer. Therefore, the entire The porous surface support of the wafer trousers, and the inconsistency of the circular variables that can be processed by JL into the machine. In addition, it can be black. More than 4L. Jutong is sucked from the pores such as dust. ^ Disadvantages due to inconsistent deformation and contamination of fast-growing substances. The paper size applies the Chinese National Standard (CNS) A4 specification (210X297 mm) ^ 7 ~~ ”------ @-批 衣------ 1T -----!) / 0 I (Fill in this page) Printed by the Consumer Standards Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs A7 B7 V. Invention Description 5 () The impact can be reduced and the wafers become less deformable. This leads to an increase in the accuracy of machining. Furthermore, avoid The system of air-type purification equipment attached to foreign matter and the cleaning support frame becomes unnecessary because it can simplify the entire equipment. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a vertical cross-sectional view of a wafer support frame according to the present invention; FIG. 2 is An explanatory diagram showing a situation in which a wafer support frame according to the present invention is used in a polishing process; FIG. 3 is an explanatory diagram showing a situation in which a wafer support frame according to the present invention is used in a honing process; FIG. 4 is a diagram The results of the honing test are shown in the formula, in which the shape of the wafer honed by the honing process of the wafer support rack of the present invention is compared with the wafer honed by the honing process using a conventional wafer support rack; And FIG. 5 is a vertical sectional view of a conventional wafer support frame. Comparison table of main components' 5 1 Support frame · 52 Porous fine particle sintered body 53 Non-porous fine particle sintered body 5 4 Exhaust duct 1 Wafer support frame 2 First porous fine particle sintered body 3 Second porous fine particle sintered The paper size applies to the Chinese National Standard (CNS) A4 specification (210X297 mm) -8-(Please read the precautions on the back before filling in this page) ------------------- Order --- f A7 ________B7 V. Description of the invention 6 () 4 Non-porous sintered body 5 Exhaust duct 6 Polishing head 8 Polishing pad 7 Polishing table 10 Honing head 11 Honing stone Employees' cooperative of the Central Bureau of Standards of the Ministry of Economic Affairs Printed a preferred embodiment The description will explain a preferred embodiment of the present invention in detail with reference to the drawings. The wafer support frame according to the present invention is used to support a fragile wafer such as a silicon wafer or a gallium arsenide wafer, and the surface of the wafer is honed or polished. Design wafer support racks to improve wafer flatness by accurately supporting wafers. That is, as shown in FIG. 1, the support surface of the wafer support frame 1 according to the present invention is divided into concentric annular regions A, B, and C from the center of the support surface to the outside in order. Regions A, B, and C are formed by the first porous fine particle sintered body 2, the second porous fine particle sintered body 3, and the non-porous sintered body 4, respectively. The porosity of the first porous fine particle sintered body 2 forming the central region A is different from the porosity of the second porous fine particle sintered body 3 forming the outer region B, and the outer region B is immediately outside the central region A. The non-porous sintered body 4 forming the outermost region C is dense or non-porous. The average diameter of the pores in the central region A is 60 to 300 microns to provide relatively large porosity 'and the average diameter of the pores in the outer region b is 2 to 50 microns to provide a porosity smaller than that in the central region A. The paper size of the central area applies the Chinese National Standard (CNS) A4 (210X297 mm) -9-(Please read the precautions on the back before filling this page) --- rl „__-- --- Order --- /线 --Λ--ΙΊ {— Printed by the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs A7 B7 V. Description of Invention 7 () The outer diameter of domain A is smaller than the diameter of the wafer (50-99%), and the outer area The outer diameter of B is larger than the diameter of the wafer (100-200%). The exhaust duct 5 is used as a vacuum tube and is formed on the bottom of the non-porous sintered body 4, so the inner end of the exhaust duct 5 reaches the first porous particles. At the bottom of the sintered body 2, the first porous fine particle sintered body 2 forms a central region A. After the wafer W is placed on the support frame 1, the gas in the central region A is exhausted through the exhaust duct 5 to vacuum support the wafer. The road 5 is not accessible to the outer area B, and the vacuum degree of the central area A can be increased. The advantage of this type of vacuum support is that even when the space between the wafer W and the support surface of the support enters dust or the like, dust Or the like is sucked in through the pores on the porous surface through the pores to avoid crystallization Deformed by dust or the like. Due to the foregoing description, the support frame 1 of the present invention is designed so that the entire wafer is supported by a porous surface in order to fully utilize the advantages of the vacuum type support frame. Furthermore, because of the central area A's The porosity is greater than the porosity of the outer region B outside the central region. The vacuum region can be effectively generated in the central region A. On the contrary, when the central region A and the outer region B have the same porosity, a problem arises, that is, if the porosity If the average diameter is increased, the vacuum zone will not be formed, resulting in a decrease in the supporting force, and if the average diameter of the pores is reduced, the performance of sucking dust or the like is degraded1, which may cause wafer degradation due to dust or the like. Paper size applies to Chinese national standard (CNS > A4 size (210X297mm, " 1〇_ --- Jf .-- ^ ---- pack--(Please read the precautions on the back. Please fill out this Page) Order 2. Printed by the Consumer Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs · A7 B7 V. Description of Invention 8 () The wafer support frame according to the present invention is manufactured by the following method. Commercially available sources The compact fine particle sintered body formed of aluminum ceramics has very low porosity. The compact fine particle sintered body is compacted into particles, and then the particles are divided into a group consisting of large particles and a group consisting of small particles. Large particle group The particles are used as the material of the first porous fine particle sintered body, and the particles of the small particle group are used as the material of the second porous fine particle sintered body. Each group of particles is mixed with a binder and glass, a binder and The glass is used as an adhesive, and the sintered mixture is used to obtain a sintered body. During the sintering, the adhesive and the glass part are evaporated to form pores. Therefore, the first and second porous fine particle sintered bodies are different due to different particle sizes and sintering conditions Porosity. Dense (non-porous) fine particle sintered bodies are manufactured in a conventional manner. Thereafter, the first porous fine particle sintered body, the second porous fine particle sintered body, and the dense or non-porous fine particle sintered body are bonded together by melting glass. Finally, the support surface is machined into a flat surface, so the wafer support frame is completed. Fig. 2 shows an example in which the support frame 1 according to the present invention is subjected to a light-polishing process. That is, the wafer W vacuum-supported by the support frame 1 is attached to the polishing head 6, and the wafer W is polished by the polishing pad 8 attached to the polishing table 7. During the polishing process, even when dust or the like enters the space between the support surface of the support frame 1 and the wafer W, the dust or the like will be sucked in, so it will not cause adverse effects such as crystal roundness. Furthermore, even when the machining pressure is applied to the wafer W, there is no difference in the amount of deformation between the central region A and the outer region B, so the flatness of the wafer W does not deteriorate. Figure 3 shows an example in which the support frame 1 according to the present invention is applied to the paper size applicable to the Chinese National Standard (CNS) A4 specification (210X297 mm) -11-'' (Please read the precautions on the back before filling in this Page) --installation --- order --- I .-- / line-,-J ----- Central Standards Bureau of the Ministry of Economic Affairs *; printed by the Industrial and Consumer Cooperatives A7 B7 __ V. Invention Description 9 ( ) Honing process. That is, in this case, the wafer W is vacuum-supported by the supporting frame 1, 'the supporting frame 1 is attached to the honing head 10, and the wafer W is honing by the honing stone 11'. Also in this case, the wafer W can be machined to have a highly flat surface. In both cases, the advantage is that there is no need to use auxiliary equipment such as air purification equipment to avoid contamination by foreign substances or cleaning support system. An example is made of a support frame such that the outer diameter of the central region A is 130 mm and the average diameter of the pores is 100 micrometers, while the outer diameter of the outer region B is 160 mm and the average diameter of the pores is 10 micrometers. . The wafer W has a diameter of 15 Omm and is honed using a supporting frame (example). Furthermore, a conventional support frame is manufactured so that the outer diameter of the central porous fine particle sintered body 5 2 is 140 mm and the average diameter of the pores is 100 micrometers, while the outer dense (non-porous) fine particle sintered body 5 3 The outer diameter is 160 mm. The same wafer W is honed using a support frame (comparative example). The examples use the support frame of the present invention and the conventional support frame used in the comparative example to compare the accuracy of machining. Figure 4 clearly shows the thickness distribution in the honing wafer. When the support frame of the present invention is used, each wafer is machined to a highly flat surface without causing flatness failure. However, none of the 100 wafers in the example had a flatness failure, and 15 of the 100 wafers in the comparative example had a flatness failure. In the embodiment described above, the central region A and the outer region B have uniform porosity, respectively. However, each area A and B can be divided into sub-regions. The paper size applies the Chinese National Standard (CNS) Λ4 specification (210X297 mm) -12- (Please read the notes on the back first and fill in this page) Order S87110 at B7 5. Description of the invention) 'In order to gradually change the porosity. The embodiment described above is just an example 'and those having the same structure and proposing the same effect and effect as those described in the scope of the appended patent application are included in the scope of the present invention I.-, lif --- „-^-^ Install an i I (please read the precautions on the back before filling out this page)-Order a one-foot I sheet of paper printed by the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs Standard 5 | Suitable " Centimeters-13-